<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>属性选择器</title>
    <style>
        div[nb=ma]{
            margin-top: 50px;
            text-align: center;
        }
        [title=jack-ma]{
            width: 200px;
            height: 200px;
        }
    </style>
</head>
<body>
    <div nb="ma">
        <img src="images/1.jpg" alt="马云" title="jack-ma">
    </div>
</body>
</html>